1. Field of the Invention
The present invention relates to a chroma signal phase correction circuitry, and more specifically to a circuitry for the phase correction of a chroma signal component of a color video signal played back from a system for playing back recorded information during an operation of jumping the recording tracks.
2. Description of Background Information
In the case of a recording medium such as a video disc, color video information is recorded on a recording track having a spiral form, in a manner such that a portion of the signal corresponding to two fields of picture information is recorded in a section of the recording track corresponding to one revolution of the recording disc.
With regard to the reproduction of the video information recorded on the video disc by means of a video disc player (VDP), several special playback modes such as a still picture playback mode and a double speed playback mode can be appropriately utilized in addition to a normal or standard playback mode.
While executing the special playback mode, it is necessary to use a jump operation by which a position on the recording medium at which the signal is being picked up is moved momentarily from a recording track portion at which the video signal is being picked up, to an adjacent recording track portion.
If the recorded signal is based on the NTSC system video signal, the difference of the phase of the chroma signal component becomes equal to 180.degree. between two sections contained in two adjacent recording track portion, each having a length of one horizontal scanning period and which are arranged side by side.
Because of this phase difference, the color of the picture image will not be correctly reproduced on a monitoring device such as a picture tube if no phase correction is applied to the chroma signal. In other words, there will be a significant color disturbance absent a phase correction.
Therefore, several methods of phase correction have been utilized in the video disc player system. However, in the case of conventinal arrangements, there have been drawbacks such that the phase of the luminance signal (Y signal) component of the video signal is also shifted by the phase correcting process of the chroma signal component. Furthermore, in order to eliminate the phase shift of the luminance signal component, it has been required to use a rather complicated circuit construction including a comb filter made up, for example, of a charge coupled device (CCD).